Science Flash Cards

A car is parked on a hill. In order to keep the car from rolling downhill, how great must the static friction acting on the car be? (Hint: Picture each scenario in your mind)

equal to the force pulling the car downhill The object is experiencing some kind of friction

A force is continuously applied to an object, causing it to accelerate. After a period of time, however, the object stops accelerating. What conclusion can be drawn?

A tug-of-war that results in one team pulling the other across the line is an example of

unbalanced forces

Acceleration is defined as the change in velocity divided by
An airplane is flying at 635 km per hour at an altitude of 35 000 m. It is currently over Kansas and is approximately 16 minutes ahead of its scheduled arrival time. What is its velocity?

time

This cannot be determined without further information.

An object is in motion when
Earth pulls on the moon and holds the moon in its orbit. The moon pulls on Earth with an equal and opposite force. This is an example of Express the following as an equation: One newton is the force that can give an object with a mass of 1 kg an acceleration of 1 m/s2.

the object changes position relative to a stationary reference point.

Newton's third law.

1 N = 1 kg

1 m/s2

Friction is defined as

force that opposes motion between two surfaces that are touching

How can the friction on a water slide be reduced?

run a constant stream of water down the slide

If the net force acting on a stationary object is zero, then the object will

remain at rest

If the net force on an object is zero then the object has
If the slope of a line on a distancetime graph is 1, the speed of the object being plotted is (Hint: Draw your own graph to visualize this idea)

balanced forces

constant

If two objects with different masses and traveling with different velocities collide, what law allows you to predict the motion of the objects after the collision?

the law of conservation of momentum

If you divide momentum by velocity, the result is the value of the object's

mass

In order to determine speed, you must know
Of the following, the greatest gravitational force would occur between On a velocity-time graph, a line with a negative slope indicates that the object is

time and distance

a loaded freighter on the high seas and Earth.

slowing down

One pound is equal to how many newtons?

4.448N

The combination of all of the forces acting on an object is called the

net force

The difference between speed and velocity is that velocity
The distance traveled by an object divided by the time it takes to travel that distance is called
The law that states that every object maintains constant velocity unless acted on by an unbalanced force is

includes direction

average speed

Newton's first law of motion.

The law that states that for every action force there is an equal and opposite reaction force is

Newton's third law of motion.

The SI unit for acceleration is

m/s2

The SI unit of force, named for the scientist who described the relationship between motion and force, is called the

newton

Weight is best described as

the downward force exerted on objects due to gravity.

What is the speed of an object at rest?
What is the unbalanced force that slows down a ball rolling across the floor? When air resistance balances the weight of an object that is falling, the velocity

0 km/h

the force of friction

remains constant.

When objects are moved further apart from each other, the force of gravity

decreases.

When the velocity of an object changes, it is acted upon by a(n)
Whenever an object is standing still, the value(s) that is/are always zero is/are

force

speed, momentum and velocity

Which is an example of balanced forces acting on an object?

a leaf lying on the grass

friction between a car's Which is an example of windshield and the air as you drive into the kinetic friction? wind

Which of the following best illustrates balanced forces? Which of the following does not indicate velocity?

A stretched rubber band being held between two hands 28 km from Los Angeles to Catalina Island

Which of the following equations is correct?

w = mg

Which of the following is not a factor in calculating momentum? Which of the following situations best demonstrates the effects of friction?

acceleration

a parachutist descending to the ground

Which of the following speeds is the most accurate?

100 meters per second

Which of the following statements is true?

Frictional forces are greatest when both surfaces are rough.

Which statement about action-reaction forces is incorrect? Which straight-line acceleration indicates an increase in speed?

They always act on the same object.

4 m/s2